US3660892A - Method for making a multi-channel magnetic head - Google Patents

Method for making a multi-channel magnetic head Download PDF

Info

Publication number
US3660892A
US3660892A US67822A US3660892DA US3660892A US 3660892 A US3660892 A US 3660892A US 67822 A US67822 A US 67822A US 3660892D A US3660892D A US 3660892DA US 3660892 A US3660892 A US 3660892A
Authority
US
United States
Prior art keywords
core
magnetic
making
magnetic head
support plate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US67822A
Other languages
English (en)
Inventor
Takashi Tanaka
Yukihiro Yanagiuchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP7308369A external-priority patent/JPS4936254B1/ja
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Application granted granted Critical
Publication of US3660892A publication Critical patent/US3660892A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/29—Structure or manufacture of unitary devices formed of plural heads for more than one track
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49021—Magnetic recording reproducing transducer [e.g., tape head, core, etc.]
    • Y10T29/49032—Fabricating head structure or component thereof
    • Y10T29/49048—Machining magnetic material [e.g., grinding, etching, polishing]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49021—Magnetic recording reproducing transducer [e.g., tape head, core, etc.]
    • Y10T29/49032—Fabricating head structure or component thereof
    • Y10T29/49055—Fabricating head structure or component thereof with bond/laminating preformed parts, at least two magnetic

Definitions

  • the two halves are' rejoined with a spacer between [58] Field of Search ..29/603; 179/ 100.2 C; them with the core parts in one half matched with correspond- 340/174 F; 346/74 MC ing core parts in the other half.
  • This invention relates to a method of making a multi-chantherebetween.
  • Each of'the core members in one half matches up with a corresponding core member in the other half to form an elementary head of a ring type.
  • the track density of the tape which is recorded and reproduced by a conventional multi-channel magnetic head is limited by the winding space and the cross-talk between the elementary heads.
  • the recent information storage requirements have increasingly required a higher track density and less cross-talk.
  • An object of the present invention is to provide a method of making a multi-channel magnetic head in which the core members are matched up exactly with corresponding core members.
  • Another object of the invention is to provide a method of making a multi-channel magnetic head in which all the magnetic gaps are aligned in one straight line.
  • a further object of the invention is to provide a method of making a multi-channel magnetic head which induces very little cross-talk between adjacent channels and can handle a tape with a high track density.
  • channel magnetic head according to the present invention 3. placing said wound magnetic core on said flat surface of spacer between the halves and with the core parts matched with the corresponding core parts in the other half.
  • FIGS. 1 and 2 are perspective views showing a method of making an elementary unit of a multi-channel magnetic head I according to the present invention
  • FIGS. 3 and 4 are a plan view and a front elevational view
  • FIGS. 5 through 8 are perspective views showing further steps in the method of making a multi-channel magnetic head according to the present invention.
  • FIGS. 9 and 10 are perspective views of other kinds of elementary units which can be used in the method of making a multi-channel magnetic head according to the invention.
  • FIGS. 11 and 12 are perspective views of stacks of other kinds of elementary unitswhich can be used in the method of making a multi-channel magnetic head according to the invention.
  • reference character 20 designates a support plate which has two flat surfaces 21 and 21a and has two openings 22a and 22b.
  • the support plate 20 is a laminated structure having a magnetic sheet 23 between non-magnetic sheets 24.
  • Reference'characters 25a and 25b designate a C- shaped and an I-shaped core member, respectively.
  • a winding 26 is wound on the C-shaped core member 25a.
  • the core members 25a and 25b are placed on the support plate 20 and joined with each other at 28 to form a ring core as shown in FIG. 2.
  • One of said two openings 22a and 22b, for example, the opening 22a receives the winding 26.
  • An elementary unit 27a is thereby formed.
  • the other opening, for example, the opening 22b is adapted to receive a winding of an adjacent unit when a plurality of units are stacked in a manner described below.
  • a plurality of units 27a which are the same as that shown in FIG. 2, and a plurality of other units 27b which are in mirror image relationship with the units 27a are stacked alternatively as shown in FIGS. 3 and 4.
  • the joints 28 of the C-shaped core members 25a and I-shaped core members 25b are nearly aligned in one straight line and lie between two planes 30a and 30b.
  • the stacked elementary units are adhered to each other by any available and suitable adhesive or by casting.
  • the stacked elementary units are cut into two halves 29a and 2912 as shown in FIG. 5 along the planes 30a and 30b which are perpendicular to the support plates 20 and parallel to each other so that each of the ring cores formed by C- shaped core members 25a and I-shaped core members 25b are divided again into two parts 25c and 25d. All the joints 28 of the C-shaped 25a and I-shaped core members 25b between said two planes 30a and 30b are thus removed.
  • the stack is cut by a blade as wide as the distance between the I planes 30a and 30b.
  • the two planes are preferably spaced 0.1-1.0 mm from each other. Cut surfaces 31 are polished flat and smooth.
  • said two halves 29 a and 29b are placed in face-to-face relationship with a. non-magnetic spacer 32 between them as shown in FIG. 6.
  • the core parts 250 and 25d in one half 29 a match up again with corresponding core parts 25d and 25c in the other half 29b to form the elementary heads in a'ring type core.
  • the spacer 32 forms magnetic gaps 33a, 33b, etc., between each pair of corresponding core parts.
  • the width of the gaps 33a, 3312, etc. is substantially equal to the thickness of the spacer 32.
  • the composite body 34 shown in FIG. 6 is enclosed in a shield case 35 to protect the multi-channel magnetic head from undesired external fields, as shown in FIG. 7.
  • Each of the plurality of windings 26 is connected to a tenninal pin 36 mounted on a terminal board 37.
  • the terminal board 37 is attached to the shield case 35 as shown in FIG. 8.
  • Said C-shaped and I-shaped core members, said magnetic sheet forming the support plate, and said shield case may be composed of any suitable and available magnetic material, such as permalloy.
  • Said non-magnetic sheets of the support plate and said spacer may be composed of any suitable and available non-magnetic material, such as BeCu.
  • Said C-shaped core member and said I-shaped core member match up exactly with each other even when said core members are thin because said two core members are joined with each other on one flat surface of said support plate.
  • the core parts in one half are made to match up exactly with the corresponding core parts in the other half by matching the halves at one point because each dimension on the cut surface of one half is exactly equal to the corresponding dimension on the cut surface of the other half.
  • the magnetic gaps are exactly aligned in one straight line.
  • the multi-channel magnetic head made by the method according to the present invention induces very little crosstalk between adjacent channels. Because the multi-channel magnetic head made by the method according to the present invention can have a small track width and a small space between the channels, it is able to handle a tape with a high track density. Said openings in the support plate help bring the individual units closer.
  • FIG. 9 wherein similar reference characters designate components similar to those of FIG. 2, two C- shaped core members 25a having windings 26 wound thereon are placed on a support plate 20. Openings 22 receive the windings 26. A plurality of units 27c which are the same as shown in FIG. 9 are stacked and adhered to each other. The steps following this step are the same as those described above.
  • a ring core 25 without a magnetic gap and having windings 26 wound thereon is positioned on a support plate 20.
  • a plurality of units 27d which are the same as shown in FIG. are stacked and adhered to each other. The steps following this step are the same as those described above.
  • the core 25 consists of one member and has no joint, there is a large tolerance in the alignment position of elementary units in the stacking process and in the cutting position of the stack of elementary units.
  • Each elementary unit 38a or 38b comprises a ring core 25 without a magnetic gap, a winding 26 wound on the core 25 and a support plate on which the core is placed.
  • the elementary units 38a and 38b are in mirror image relationship with each other.
  • Each pair of adjacent units 38a and 38b are offset from the other; alternate units 38a and 38a or 38b and 38b are aligned with each other and have an open space 39 between them.
  • Electrical parts (not shown) other than the parts of said magnetic head are accommodated in the open space 39.
  • the electrical parts are preferably a transformer and/or an amplifier in the form of an integrated circuit which cooperate with each winding 26.
  • a combined transformer can reduce the number of turns of the winding 26 as well as the cross-talk.
  • the stack is cut at the plane 40, shown by broken lines in FIG. 11, which is perpendicular to the support plates 20 and which divides each ring core 25 into two parts, C-shaped part 250 and I-shaped part 25d. The steps following this step are the same as those described above.
  • each ring core 25 with a winding 26 is placed on a flat surface 21 of a support plate 20a.
  • the support plate 20a has a thinner portion 41 and a thicker portion 42.
  • a plurality of elementary units are stacked in a staggered arrangement as shown in FIG. 12.
  • the thinner portion 41 of each said support plate 20a overlies the next lower support plate 20a, and the thicker portion 42 overlaps an edge 43 of the next lower support plate 20a or extends below the upper surface 21 of the next lower support plate 20a and abuts the edge 43 of said next lower support plate 20a.
  • Such a construction makes it easy to stack a plurality of elementary units.
  • the stack is cut in a plane 40, shown by the broken line in FIG. 11, which is perpendicular to the flat surfaces 21 of the support plates 20a and which divides each ring core 25 into two parts, C-shaped part 25c and I-shaped part 25d.
  • the steps following this step are same as those described above.
  • a method of making a multi-channel magnetic head comprising:

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Magnetic Heads (AREA)
US67822A 1969-09-10 1970-08-28 Method for making a multi-channel magnetic head Expired - Lifetime US3660892A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP7308369A JPS4936254B1 (de) 1969-09-10 1969-09-10
JP5926270 1970-07-06

Publications (1)

Publication Number Publication Date
US3660892A true US3660892A (en) 1972-05-09

Family

ID=26400316

Family Applications (1)

Application Number Title Priority Date Filing Date
US67822A Expired - Lifetime US3660892A (en) 1969-09-10 1970-08-28 Method for making a multi-channel magnetic head

Country Status (5)

Country Link
US (1) US3660892A (de)
CA (1) CA944544A (de)
DE (2) DE2065746A1 (de)
FR (1) FR2061179A5 (de)
NL (1) NL7013347A (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3737993A (en) * 1970-11-27 1973-06-12 Matsushita Electric Ind Co Ltd Method of making a multi-channel magnetic head
US3783504A (en) * 1969-08-14 1974-01-08 Bull General Electric Process of fabricating multichannel magnetic head units
US3787963A (en) * 1973-02-05 1974-01-29 Honeywell Inf Systems Method of fabricating a multi-head magnetic transducer assembly
US3893189A (en) * 1974-01-14 1975-07-01 Spin Physics Inc Magnetic record/reproduce head and manufacturing method therefor
US3983622A (en) * 1974-01-10 1976-10-05 Eastman Kodak Company Method of manufacturing magnetic record/reproduce head
DE2820383A1 (de) * 1977-05-12 1978-11-30 Matsushita Electric Ind Co Ltd Zusammengesetzter magnetkopf
EP0035542A1 (de) * 1979-09-04 1981-09-16 Minnesota Mining & Mfg Konstruktive ausbildung eines magnetkopfes für einen aufzeichnungsträger mit mehreren spuren.

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5634128A (en) * 1979-08-23 1981-04-06 Rca Corp Multiple magnetic head for record*reproduction device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3064333A (en) * 1959-06-29 1962-11-20 Ibm Method of making a magnetic transducer
US3545077A (en) * 1967-12-04 1970-12-08 Victor Company Of Japan Method of making multiple-element magnetic head

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3064333A (en) * 1959-06-29 1962-11-20 Ibm Method of making a magnetic transducer
US3545077A (en) * 1967-12-04 1970-12-08 Victor Company Of Japan Method of making multiple-element magnetic head

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3783504A (en) * 1969-08-14 1974-01-08 Bull General Electric Process of fabricating multichannel magnetic head units
US3737993A (en) * 1970-11-27 1973-06-12 Matsushita Electric Ind Co Ltd Method of making a multi-channel magnetic head
US3787963A (en) * 1973-02-05 1974-01-29 Honeywell Inf Systems Method of fabricating a multi-head magnetic transducer assembly
US3983622A (en) * 1974-01-10 1976-10-05 Eastman Kodak Company Method of manufacturing magnetic record/reproduce head
US3893189A (en) * 1974-01-14 1975-07-01 Spin Physics Inc Magnetic record/reproduce head and manufacturing method therefor
DE2820383A1 (de) * 1977-05-12 1978-11-30 Matsushita Electric Ind Co Ltd Zusammengesetzter magnetkopf
EP0035542A1 (de) * 1979-09-04 1981-09-16 Minnesota Mining & Mfg Konstruktive ausbildung eines magnetkopfes für einen aufzeichnungsträger mit mehreren spuren.
EP0035542A4 (de) * 1979-09-04 1982-01-11 Minnesota Mining & Mfg Konstruktive ausbildung eines magnetkopfes für einen aufzeichnungsträger mit mehreren spuren.

Also Published As

Publication number Publication date
CA944544A (en) 1974-04-02
FR2061179A5 (de) 1971-06-18
DE2065746A1 (de) 1975-09-11
NL7013347A (de) 1971-03-12
DE2044408A1 (de) 1971-05-13

Similar Documents

Publication Publication Date Title
US3660892A (en) Method for making a multi-channel magnetic head
US2618709A (en) Cylindrical contact magnetic head
JPS6252361B2 (de)
US2658114A (en) Magnetic recording-reproducing device
US3807042A (en) Method of making a magnetic head structure
US3564153A (en) Magnetic transducer with oppositely oriented heads and two core holders
GB1339415A (en) Magnetic head and method of manufacture thereof
US3978523A (en) Multi-channel dual-gap magnetic head
US3716677A (en) Multi-channel magnetic head
US3854199A (en) Manufacture of magnetic transducing heads
US2927974A (en) Magnetic transducer
US3238603A (en) Method of manufacturing a magnetic transducer
US3185971A (en) Double magnetic head
US3672044A (en) Multi-channel dual-gap magnetic head
US3249928A (en) Magnetic transducer
US3082509A (en) Method of constructing magnetic recording devices
US4472752A (en) Magnetic head
US3065311A (en) Magnetic transducer
US3921219A (en) Multi-channel magnetic head
US3783504A (en) Process of fabricating multichannel magnetic head units
US3679839A (en) Two track multiple element magnetic head
US4300178A (en) Multichannel magnetic head
US3737993A (en) Method of making a multi-channel magnetic head
US3678576A (en) Method of manufacturing multiple track, single gap magnetic heads
GB879600A (en) Multiple track magnetic recording head